Multiphase electric motor.



H. GBARING. MULTIPHASE ELECTRIC MOTOR. APPLICATION I EILED'AUG.10, 1912. 1,103,501, Patented July 14,1914.

3 SHEETS-SHEET l WITNESSES H. GEARING.

MULTIPHASE ELECTRIC MOTOR. APPLICATION FILED AUG. 10, 1912.

Patented July 14, 191i 3 SHEETSSHEET Z.

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WITHESTZES {I n/la fifijiz VZ/ f jENToR H. GEARING. MULTIPHASE ELECTRIC MOTOR.

I I APPLICATION FILED Ammo, 1912. 1 1 03,501 Patented July 14, 1914.

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INVEN OR wlmssszs I UNITED STATES PATENT OFFICE.

'HAIRY "GEAB iNG, OF LOS ensures, CALIFORNIA, Assreuon or ONE-FOURTH T0 CHARLES J. ONE-ILL AND ONE-FOURTH TO GILBERT r. BITTER, BOTH or THE 1 prs'rmcr or COLUMBIA.

To all whom it may concern of Great Britain and Ireland, residing at Los Angeles, in the county of Los Angeles and State of California, have invented certain new and useful 'Improvements in Multiphase Electric Motors; and I do hereby declare the following to be a full, clear, and

exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same. The invention relates'to improvements in multiphase electric motors and means for controlling the same, whereby the power delivered by the motor may be selectively varied to accommodate different working 'trol circuits.-

conditions. A practical exemplification of the application of the invention to an induction motor is illustrated in the accompany ing drawings, in which; I

Figure 1 is a diagrammatic side elevation of the stator androtor and the windings thereon. Fig. 2 is a vertical section through the upper half of the motor. Fig. 3 is a diagram of the motor windings and the con- J Figs. 4 to 10 illustrate dia-v grammatically the circuit connections of the stator windings for varying-the power 'de-' veloped by the-motor. and as effected by the controller.

Referring to the drawings, A indicates the stator or field which may be constructed in any preferred or wellknown manner, and B is the rotor or armature.

0 indicates the field frame, D the armature spider. v

E designates the stator winding controller,

. F the reversing controller and G the resistance coils.

Mounted on the stator A are two separate windings, l and 2, the winding 1 being connected by leads 3 with stationary contacts 5 on the controller E,- and. windings 2 are severally connected by leads 4 with similar contacts 6 upon the controller. The armature conductors 7 ot'the phase-wound type, are provided-with leads 8 whi.ch are severally connected to resistance-G by means of sliding contacts 9. v

Mounted inthe controller E adjacent the contact blocks 5 aud t; are a series of stationary contacts 20 and 21 which are adapted to be connected to blocks 6 and 5 respec- MUL-TIPHASE ELECTRIC Moron.

I Specification of Letterslatent. H 'I fatentefl J 1y 14 1914. Application filed August 1Q, 1912. Serial No, 714,363. I

I i tively, by means of the contact blocks 10 to Be it known that I, HARRr GnA nNo, a' subject of'theKingof the United Kingdom 19 inclusive carried by the movable member of the controller, which is preferably of the ordinary barrel type, the said contacts 10 to 19 inclusive being distributed and. arranged in horizontal and vertical rows, as indicated in Fig. 3, the several connections thus established serving to connect one or both of the stator windings 1 and 2 in va-.

rious orders and arrangements, as will be more partlcularly explained hereinafter.

The leads from the power circuit indicated by numerals 25, 26 and 27 are adapted to be connected to the stationary contact blocks 20 and 21 as follows; two intermediate contact blocks 20 are connected by leads 22, 22 and lead 24 directly to the main powerdead 25, and similarly the two intermediate contact blocks 21 are connected by leads 23, 23 and lead 2% to said main lead 25. The-two outside pairs of contact blocks 20 and 21 are connected by leads '22 and 23 respectively through leads 28 and 29 and reversing controller F to the main leads 26' and 27.-

, The reversingcontroller F may be of any preferred form and as diagrammatically represented, consists of stationary contacts 35 and 36 adapted to be bridged by movable contacts 31 and two sets of stationary -contacts 33 and 34 cotiperating with bridging contacts 30.

Inthe practical construction of the apparatus, it is preferable thatthe movable contacts 30 and 31. and the resistance contact fingers 9 be mounted on the same controller drum so that when the circuit to the stator windings is closed, all of theresist-ance G, represented by the coils 32, is-connectecl in the circuit of the rotor.

drumcontacts-30 into bridging relation bethe resistance G is maintained in the rotor circuit and the handle of controller F may .be still further operated to gradually cut out the resistance G without disturbing the closed relation of contacts 30, 33 and 34. Similarly, when a reversal ofthe controller F is desired and contact is broken at 33 and 34 and made at 35 and 36, the resistance G is all cut into the circuit of the rotor before theoconta-ct is broken at 30 and made at 31,

For example, when the controller F- is operated to bring the which has the efi'ectof preventing a rush of current through the rotor circuit and also 26 and 27 to the stator winding 2,

tends to cut down the speed of the motor to prevent heavy shocks and jars in the actual reversal of the movement of the rotor. ter reversal has been effected at the controller F, the resistance G may be gradually cut out without disturbing the relation of contacts 31, and 36, so that the motor may be brought up to speed or the speed may be regulated as desired by merely shiftingthe handle of controller F.

As l'iereinbefore indicated, the power controller E is provided with a series of movab e contacts 10 to 19 inclusive to cooperate with the fixed contacts 5, (i, 20 and 21 to effect different arrangements and combinations of the stator windings 1 and 2, and thereby selectively vary the power developed by the motor to meet the different conditions of work to be performed.

Asillustrated in the diagram, when the power controller E- is moved to its first point the contacts 10 bridge contacts 6 and 20 and close-the circuits from the mains 25, so that the latteris connected to the power circuit in Y form or arrangement, as shown in Fig. 4. Upon moving the controller E to the second point, the winding 2 is connected in delta form through the set of movable contacts 11, as in Fig. 5. \Vhen the controller is moved to thethird point, the stator winding lis connected to the main leads through the series of contacts 19 in Yarrangement, see Fig. 6. For the fourth-position 'or point of the controller, the winding 2 is connected to "the main leads in Y form through the series of contacts 12, and the stator winding 1 is connected in Y- form to the main leads through the series of "contacts 18, the two windings 1 and 2 therefore being connected to the main leads in parallel as illustrated in Fig. 7. When the controller handle is shifted to the fifth point, the winding 1 is connected in delta form through the series of contacts 17 see Fig. 8. Upon movement of the controller to the sixth point, the winding 2 is connected in Y form through the series of contacts 13 and the winding 1 is connected in delta form through the series of contacts 16 see Fig. 9. When the controller handle is moved to the seventh point, the winding 2 is connect-ed in delta form through the contacts 14 and the winding 1 is also connected in' delta form through the contacts 15 see Fig. 10. From the foregoing, it will be seen that by properly operating the controller E, seven different connections of the windings 1 and 2 resulting in seven distinct changes of power developed by'the motor may be effected. Preferably the coils or windings 1 and 2 of the stator differ from each other in the number of turns in each, the winding 1, as represented, having the larger number of turns, whereby a wider variation in the power developed may be effected than if the two coils or windings were of the same size.

From the foregoing, it will also be apparent that the seven different powers may be obtained by manipulating the controller E and these same powers may be-ennployed ither in a forward or reverse direction of the rot-or by properly operating the revcrsing cont-roller F and that the speed of the motor may be accurately regulated by cuting in or out the resistance G, which is effected by means of the handle of the revers ing controller F, as will be understoodl To illustrate byconcrete example, the possibilities of power variation in a motor of the character described, let it be assumed that the motor develops a maximum horse )ower of 30 and that the small coil or winding 2 of the stator contains approximately onehalf as many turns as the larger coil or winding 1. Upon connecting the small coil 2 in Y, the Hi P. developed will be 5.77;

with a small coil alone in delta, the H. P.

will be 10; with the large coil 1 only in Y connection, the H. P. will be 11.558; with the large coil only-in delta connection the H. P. will be 20. l/Vith both coils land 2 in Y connection, the H. P. will be 17.332;

with both coils 1 and 2 in combination, delta connected, the H. P. will be 30; with the small coil 2 in delta connection in combination with the large coil 1 in Y connection, the H. P. will be 15.774; with the small coil in Y connection in combination with the large coil in delta, the H. P. will be 25.774. From the foregoing, it will be apparent that the seven different powers indicated may be readily and economically obtained. while the coils or windings are being worked at their regular capacity and without resistance in series.

While my invention has been explained with reference to a motor having but two sets of coils or windings upon the stator, it is to be understood that this special case has been chosen merely. for the purposes of illustration, and that more than two sets of windings upon stator may equally well be employed.

\Vhat I claim is l 1. The combination with .a multiphase electric motor having a rotor winding and separate stator windings, of adjustable means for connecting the individual stator" windings in Y or in delta arrangement with the power circuit and for connecting said winding to sald power circuit in various combinations of Y, Y-dclta, or delta-delta,

whereby the power developed by the motor may be selectively varied.

2. The combination with a multiphase electric motor having a rotor winding and separate unequal stator windings, of adjustable means for connecting the individual stator windings in Y or in delta arrange ment with the power circuit and for connecting said windings to said power circuit in various combinations of Y, Y-delta, or delta-delta, whereby the power developed by the motor may be selectively varied.

3. The combination with a multiphase electric motor having a rotor winding and separate stator windings, of a controller having fixed and movable contacts to connect the stator windings-with the power circuit individually in Y or in delta relation and jointly in various combinations of Y, Y-delta, or deltaalelta, whereby the power of the motor is selectively varied.

l. The combination with a multiphase electric motor having a rotor winding and separate stator windings, of adjustable means for connecting the individual stator windings in Y or in delta arrangement with the power circuit and for connecting said windings to said power circuit in various combinations of Y, Y-delta, or delta-delta,

whereby the power developed by the motor may be selectively varied, and a reversing switch in the stator circuit.

5.- The combination with a multiphase electric motor having a rotor winding and separate stator windings, 'of adjustable means for connecting the individual stator windings in Y or in delta arrangement with the power circuit and for connecting said windings to said power circuit in various combinations of Y, Y-delta, or delta-delta, whereby the power developed by the motor may be selectively varied,'a regulable external resistance in the rotor circuit, and a reversing switch in the stator circuit adapted to cut the resistance into the rotor circuit with each reversal of the stator circuit.

In testimony whereof I aflix my signature, in the presence of two subscribing witnesses.

HARRY GEARING.

Witnesses r J 'NoIT. HARRINGTON, H. C. Rnssnnn. 

